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From 5e76619fcda3d792b2cb188fc2d950c61d7ebf09 Mon Sep 17 00:00:00 2001
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From: David Sterba <dsterba@suse.com>
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Date: Tue, 21 Jul 2020 12:28:05 +0200
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Subject: [PATCH 2/2] btrfs-progs: mkfs: switch to single as default profile
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for multiple-devices
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The single profile is better suited as default for data on multiple
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devices. Switch from RAID0 because:
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- it's easier to convert to other profiles, as single consumes some
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chunks per device, but RAID0 has chunks on all devices regardless of
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the used space
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- RAID0 has no redundancy and compared one disk failure affects many
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files due to striping, while with single the chances are a bit higher
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that complete files are stored on one device
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- when the device sizes are not equal and not even close to equal, the
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maximum achievable size with RAID0 is size of the smallest device due
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to striping, with single it's the sum of all device sizes
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The changed defaults could affect scripts and deployments that rely on
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the old values, but given the number of possible profiles for multiple
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devices let's hope that they're specified explicitly in majority of
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cases.
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Issue: #270
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Signed-off-by: David Sterba <dsterba@suse.com>
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(cherry picked from commit f1507716c67e2d6012f1e7a0f1538d4f669faa23)
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---
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mkfs/common.h | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/mkfs/common.h b/mkfs/common.h
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index 61969dcc..cc88db71 100644
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--- a/mkfs/common.h
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+++ b/mkfs/common.h
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@@ -35,7 +35,7 @@
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#define BTRFS_MKFS_DEFAULT_META_ONE_DEVICE BTRFS_BLOCK_GROUP_DUP
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#define BTRFS_MKFS_DEFAULT_META_ONE_DEVICE_SSD 0 /* SINGLE */
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-#define BTRFS_MKFS_DEFAULT_DATA_MULTI_DEVICE BTRFS_BLOCK_GROUP_RAID0
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+#define BTRFS_MKFS_DEFAULT_DATA_MULTI_DEVICE 0 /* SINGLE */
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#define BTRFS_MKFS_DEFAULT_META_MULTI_DEVICE BTRFS_BLOCK_GROUP_RAID1
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/*
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--
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2.26.2
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